Question: Is the earth ever going to stop spinning?

Columbus Flight Directors answered on 13 Oct 2015:

Simon: Hi Annabanana: Good question! The Earth’s rotation is infact slowling down… but very very slowly. However it is unlikely to slow down completely before it is engulfed by the Sun in about 5 billion years from now.

More likely is that the Earth will “tidally lock” with the Sun or more probably with the Moon. Tidal Lock is when a celestial bodies rotation cycle is the same time as its orbital cycle it has around its parent star or planet.

The Moon is already “tidally locked” to Earth which is why we always see the same face of the moon pointing towards us. Although the Earth is more massive than the Moon, the relative mass between two actually makes them more a binary planetary system than a traditional planet/moon system so that tidal locking of the Earth to the Moon is also possible.

The Earth could also tidally lock to the Sun. If this happens it will present significant challenges for life on Earth since one half of the planet will be in constant daylight (exposed to temperatures of plus 100s of degrees) and one half in constant shadow (exposed to temperatures of minus 100s of degrees). You may then expect to have a barren desert like planet on one side and a frozen wasteland on the other but we also have a thick atmosphere around the planet which would allow mixing of the air between the two hemispheres and so some kind of gobally stable climate maybe possible but for sure it will be pretty violent weather along the terminator of the two hemispheres… divided perhaps by lines of tornadoes or thunderstorms!